This invention relates to the field of radiological imaging and, more specifically, an object of interest particularly in the field of mammography. Mammography is largely used for detecting lesions and preventing breast cancer. The first signs that radiologists search for on mammogram images are calcium deposits called micro-calcifications, which generally constitute more opaque elements in X-rays than the surrounding tissue. Radiologists scrutinize the images looking for signs of these micro-calcifications. Radiologists can, to a certain degree, differentiate between malignant micro-calcifications (often a group of clusters) and benign calcium deposits. Radiologists interpret the shape and brightness of each individual micro-calcification as well as the shape and extension of the clusters they observe on radiographic images.
Nevertheless, some radiologists do not perceive certain deposits. This phenomenon has several causes. Notably, because mammogram images are the result of projections, they represent superimposed structures that block the visibility of micro-calcifications. Furthermore, radiologists must often analyze several mammography images one after the other, which could lead to eye fatigue that could affect their capacity to perceive clusters.
Computer Assisted Diagnostics (CAD) tools help radiologists in detecting and characterizing lesions. Such a system is, for example, described in U.S. Pat. No. 6,137,898. These CAD systems can process film images that have been previously digitalized using a scanner and detect malignant micro-calcification clusters. These systems indicate the position of clusters on the image using markers such as rectangles or circles, or even arrows, placed around the clusters. The radiologist can select the area thus marked to view in more detail. These systems include algorithms based on characteristic parameters that allow them to automatically distinguish the malignant elements from the benign elements. The inconvenience of these systems is that they tend to replace the radiologist in the interpretation of the image, in particular, in terms of distinguishing between malignant elements and benign elements. Nevertheless, these systems are not sufficiently reliable to completely replace radiologists.